1. Field of the Invention
The invention relates to the field of marking an area on the body of a patient as a guide for medical treatment. More particularly, the invention relates to marking the skin of a patient in preparation for medical treatment. Most particularly yet, the invention relates to applying marks to the skin of a patient undergoing radiation therapy.
2. Description of the Prior Art
Markings, also often referred to as tattoos, are typically applied to the skin of a patient in preparation for radiation therapy or other medical treatment, as a means of clearly delineating the location of treatment set-up points. Traditionally, the marking is done by applying a drop of marking agent to the surface of the patient""s skin and then penetrating the skin with a needle to allow the marking agent to flow under the surface of the skin. The size of the needle used can vary widely, some technicians preferring to work with a larger needle, others with a smaller needle. When marking the skin in this way, it is critical that the marking agent, such as India ink, as well as the needle tip be sterile. Furthermore, it is highly desirable to have a disposable needle, to eliminate the possibility of passing pathogens from one person to another and to eliminate the need for sterilizing the needles. It is also desirable to have a marking device that will accept a standard needle that is typically kept in stock in a healthcare facility, in a range of needle gauges.
Sarath et al. (U.S. Pat. No. 4,798,582; 1989) discloses a needle cartridge that is threadably mounted onto the drive shaft of an electrical tattooing instrument. Chasan (U.S. Pat. No. 5,496,304; 1996) discloses a surgical marking pen for drawing lines on the skin of a patient. The Chasan device has a handle and a fluid reservoir that communicates with a pinwheel that penetrates the skin. Arranged around the circumference of the pinwheel is a plurality of needle tips that puncture the skin, leaving a tattooed line in the epidermis of the skin. The marking pen disclosed therein may be disposable, or refillable. The disadvantages of these devices are that they require special equipment or special needles. The device disclosed in Chasan has the further disadvantage of not being suited for placing individual circular or triangular markings on the skin, that is, it is a device that draws lines, rather than marks points.
Rosen (U.S. Pat. No. 6,056,737; 2000) discloses a disposable skin-marking device that is provided in a sealed sterile package and is discarded after a single use. The skin-marking device has a felt-tip nib and includes a glass cartridge containing marking agent inside a flexible housing. The cartridge is ruptured by bending or compressing the housing, whereupon the marking agent flows into the nib of the pen. This type of device is not suited to applying a marking agent under the surface layer of the skin.
Therefore, what is needed is a skin-marking device for applying a marking agent beneath one or more layers of the skin. What is further needed is such a device that provides a sterile supply of the marking agent and is disposable after a single use. What is still further needed is such a device that accepts a standard general-purpose needle in a range of needle gauges.
For the above cited reasons, it is an object of the invention to provide a disposable sterile skin-marking device that carries a cartridge of sterile marking agent and uses a needle to apply the marking agent beneath one or more layers of the skin surface. It is a further object of the invention to provide such a skin-marking device that will accept a standard needle in a range of needle gauges.
The object of the invention is achieved by providing a skin-marking device that has a flexible housing provided with a quick-coupling type of coupler that is adapted to receive a needle provided with a base that mates with the quick-coupler on the housing. In the Preferred Embodiment, the quick-coupler is a LUER-LOK type coupler and the housing has a female coupler and the needle base a male coupler. Any one of a range of needles provided with a LUER-LOK type base can be inserted into the needle end of the skin-marking device. Alternative embodiments may include other types of standard coupling mechanisms that needles are typically provided with when supplied to healthcare facilities. Thus, needles in a range of needle gauges are available to the technician preparing the patient for the radiation therapy and he or she can choose the preferred needle size. The device is supplied packaged in sterile, protective material.
The flexible housing contains a sealed rupturable cartridge that contains sterile marking agent, such as India-ink. The cartridge is ruptured by flexing or compressing the housing, while the needle sheath is still intact and in place. The marking agent flows into the needle and, after removing the sheath, the needle is used to penetrate the skin of the patient to apply the marking agent. The cartridge contains sufficient marking agent to apply multiple tattoos to a single patient. The entire device including needle is discarded after use.
The skin-marking device is provided as a sealed, sterile unit that includes the housing, the cartridge with marking agent, a seal cap at the end of the housing, a LUER-LOK tip for receiving a needle, and a LUER-LOK cap to seal the needle end of the skin-marking device before use. When ready to apply the tattoo to the patient, the LUER-LOK cap is removed, a needle with a LUER-LOK base is fitted into the LUER-LOK tip of the device, and the housing flexed to rupture the sealed cartridge with the marking agent. The marking agent flows into the needle, and the technician can now remove the needle sheath and apply the marking agent beneath one or more layers of the skin to precisely mark the location for treatment setup.
In a first alternative embodiment, the quick-coupler on the housing of the skin-marking device is provided with a needle tip that is short enough that a needle with a base that mates with the quick-coupler may be fitted over the short needle. This is an advantage in that the skin-marking devices may be provided with a typical gauge needle tip for skin-marking, but a technician who has a preference for a longer needle or a different gauge needle may attach the preferred needle to the skin-marking device without having to remove the short needle tip.
In a further alternative embodiment of the present invention, the skin-marking device can be supplied as a disposable, ready-to-use unit that includes a flexible housing with a cartridge of sterile skin-marking agent, without a quick-coupler, and already fitted with a standard gauge needle for skin-marking.